Without limiting the scope of the invention, its background is described in connection with anti-parasitic vaccines.
Malaria and related parasitic diseases continue to bring misery to much of the world's population. Malaria and related parasitic protozoa cause untold human misery worldwide. It is estimated that over 1 billion people are infected with the malaria-causing organism, Plasmodium, and 3 million persons die each year from the disease (Breman et al., 2004). Those who do not die endure long suffering. The disease causes billions of dollars in lost productivity. Humans with Sleeping Sickness, Chagas disease, Cryptosporidiosis, and Toxoplasmosis also suffer greatly. Many people die from the diseases, or lose their ability to be productive members of their communities. Similarly, these and other parasites annually kill large numbers of the vertebrates (cows, sheep, goats, sheep, pigs, and chickens) that are human primary food sources worldwide (Roberts and Janovy, 2005).
Several methods are being used to roll back malaria and other of these parasitic diseases, including reduction of insect vectors, drugs, and vaccines. None of these are completely effective, though, and it is estimated that more humans are infected now with malaria than were infected 20 years ago. One problem with existing vaccines is that they target surface antigens of poorly understood or unknown function. In addition, the targets mutate and render the organism resistant to the vaccine. Therefore, new discoveries and new approaches are essential to combat malaria and related parasitic protozoan diseases.